Last week we learned the importance of reading the directions and touched on the difference between weight and volume. This week we’re gonna go into that more.
When measuring ingredients you can do it by one of two ways: Weight or Volume. Which you choose depends on what kind of ingredient needs to be meted out.
Weights are, obviously, done with a scale and you can pick up a decent digital scale that does both grams and ounces/pounds for not too much of an investment.
Liquids will (almost) always be measured by volume. They have this pesky habit of not holding a shape that makes them tough to pile on a scale.
The smallest unit is an ounce (abbreviated oz.) and, yes, that’s a shot glass in the picture to the left. It makes it a cinch to measure ounces and the fractions thereof.
8 oz. (sometimes written as fluid ounces of fl. oz.)=1 cup
2 cups = 1 pint (pt)
2 pints = 1 quart (qt)
4 quarts = 1 gallon (gal)
If you need more than that, well, you’re dealing in serious quantities and why do you need this lesson?
They can also be measured by teaspoons and tablespoons (3 tsp = 1 Tbsp, 1 Tbsp = 1 ounce) but you usually get into this with extracts and specialty oils.
Oh, and the above? That’s all Imperial measures, what we use here in the US and every other place that hasn’t gone Metric. Metric uses that nice base-10 systems where everything can be broken down infinitesimally from their main unit of a Liter. Maybe we’ll do Metric another day.
Let’s march on. In an Imperial fashion.
Dry ingredients can be measured by volume–in cups–or by weight–ounces and pounds or (Metric) grams.
So, if you can measure both liquids and dry bits in cups, why do you need two different sorts of measurers?
Simple: the flat-topped dry measures allow you to scoop the flour, sugar, etc. into the correctly-sized cup and then, with a straight implement of some sort (the back of a butter knife, your finger, whatever) scrape off the excess. This gives you an exact cup (or whatever). Liquid, on the other hand, has that tendency to spill over edges plus doesn’t tend to form a flat top. In order to accurately measure liquids you need to be able to see through the vessel (which is why so many are glass or clear plastic) at eye level to see exactly where the curve is in the center–that’s the actual measure of what’s in the glass (technically known as the meniscus).
That, and using the big liquid measures for dry invites the habit of shaking and, thereby, compressing the ingredients within. Something you generally don’t want to do.
Now, what’s the difference between fluid ounces (liquid) and weighted ounces (dry)? Isn’t a cup a cup no matter what?
If you were to weigh the amount of flour that a single cup of the dry type contains, it’d actually be closer to 4 ounces in weight, not the 8 ounces of volume you’d expect. See the problem?
Let’s go back to our cheese example from last week: an 8 ounce (weight) block of cheddar will, when shredded, yeild 2 cups (volume) or more. And not even food related, just imagine how much more of, say, feathers you’d have to have to weigh a pound compared to, say, lead. It’s sorta like comparing a pound of pork to a pound of raw baby spinach–there’s a BIG difference.
If it’s a dry ingredient (or at least not liquid–moist, like brown sugar or shredded pork, still coints as dry) and it says ounces, weigh it.
Finally, is there any time you can substitute volume for weight one-to-one?
Yes–water and things of similar ilk fall to this little ditty:
A pint is a pound the whole world round!
A fluid pint is 2 cups, 16 ounces. A pound is 16 ounces. This is one of those times when they are, truly, equal. So on the rare chance your making something that calls for 2 pounds of water (or similar liquids–cream is heavier than water, but skim milk is pretty close to the original: thicker is denser is heavier) you know you can use 2 pints or half a gallon and you’re golden!*Incidentally, the slidey small dry measures are great to have around–no juggling the various sizes, one tool has ’em all (well, one for teaspoons and one for tablespoons). They’re not great for liquids, though–the wet bits can seep under the barrier and make a mess.